上海：先有船，后有楼

The most common photograph of Shanghai is taken from the Bund, looking east.

A row of early twentieth-century stone buildings stands behind you; across the water is the cluster of Pudong skyscrapers, and after dark the whole skyline starts changing colour.

The photograph is very useful, because it compresses a complicated city into one easily grasped sentence: the old is on this side, the new is on that side.

The trouble is that while the sentence isn't false, it explains almost nothing.

If you want to know what the relationship between these two banks actually is, the cheapest method is to spend two yuan on the ferry.

The ferry is municipal transport; the fare is the same as a bus.

At morning rush hour the deck is packed with commuters, delivery riders and people wheeling bicycles.

They keep their heads down over their phones, entirely uninterested in the skyline on either side.

For them this is simply crossing the river.

But the dozen-minute crossing passes precisely through two upheavals in a century and more of Shanghai's history.

Start with the boat.

Public ferry service on the Huangpu opened in 1911.

Before that, wharves and factories were already going up in Pudong, and employers used small steam launches to carry workers across.

Until the Dapu Road Tunnel opened in 1971, the ferry was the only way across the river.

The Yan'an East Road Tunnel opened in 1989, and bridges and metro lines followed.

The ferry peaked in the 1980s: over a million passenger trips a day, with twenty-two routes across the water.

The 1993 annual figure was roughly three hundred and seventy million trips.

A ticket then cost six fen; today it is two yuan.

Board today and you will most likely find a seat.

A mode of transport went from monopoly to margin in about thirty years.

The west bank is the Bund.

That row of buildings was put up between the end of the nineteenth century and the 1930s, belonging then to banks, trading houses, insurance companies and newspaper offices.

Shanghai in that period was one of the most important treaty ports in the Far East, with foreign capital, compradors and local merchants operating on the same street.

The architectural styles came from Europe, the drawings from foreign firms, and the construction was carried out by Chinese craftsmen.

Calling this stretch of history simply glorious or simply humiliating leaves out an enormous amount of detail.

It contains trade, wealth, unequal treaties and the migration of a great many ordinary people, all at once.

The east bank is Pudong.

On 18 April 1990, China announced the development and opening of Pudong, establishing the Lujiazui, Waigaoqiao and Jinqiao national-level development zones that same year.

Before this, Pudong was mainly farmland, wharves, warehouses and small factories.

A saying circulates in Shanghai: better a bed in Puxi than a room in Pudong.

The Oriental Pearl was completed in 1994 at four hundred and sixty-eight metres, the city's high point at the time.

Today's high point is the Shanghai Tower, at six hundred and thirty-two metres.

In a little over thirty years, farmland became China's tallest skyline.

So the difference between the two banks of the Huangpu isn't only a matter of sequence in time.

It records two openings of different character: one led by outside capital, one driven by state planning.

Once you see that, the phrase "new versus old" starts to look far too crude.

In the afternoon I left the riverside and walked into a longtang in the old town.

The longtang is a housing form particular to Shanghai: a main lane leads inward, flanked by tightly packed two- and three-storey shikumen.

It was not a nostalgic object for a minority; it was once how this city mainly lived.

In 1949, Shanghai had roughly nine thousand two hundred shikumen lanes, more than two hundred thousand buildings, covering around twenty million square metres.

In that year about seventy to eighty percent of the city's population lived in them.

Walk in today and you will see several states existing at once: houses still occupied by their old residents, houses converted into cafés and guesthouses, and whole districts demolished.

The statistics are not consistent, but more than eighty percent have been demolished, and only around one thousand nine hundred reasonably intact examples survive.

The point genuinely worth noticing is the timing.

Block-by-block demolition began around 1990.

In other words, the same period in which Pudong's development was announced was the period in which Shanghai began clearing shikumen at scale.

Building a new city on the east bank, demolishing the old city on the west: these are usually narrated separately, and are in fact two faces of a single decision.

In one lane I talked for a while with an older woman who had lived there over forty years.

I asked whether she would be willing to move, and her answer was far more complex than I had expected.

She began with a list of drawbacks: small rooms, cold winters, an inconvenient bathroom, a roof that leaks in the rain.

Then she said she knows every single person in the lane.

After moving into a new estate the flat would certainly be larger, but she might not exchange more than a few sentences with a neighbour in a year.

She said that when people discuss old housing, they usually discuss only the housing itself.

What is genuinely hard to reproduce is the relationships built up between people over a long time; once broken apart, they are very hard to grow again.

That remark made me look at the contrast between the Bund and Pudong differently.

We are used to telling Shanghai as a story about speed: a new city raised in thirty years.

The speed is real, and so is the achievement.

But speed always has a cost, and the cost is usually not distributed evenly — it lands on particular families and particular blocks.

Whether a city's heritage protection is any good can't be judged only by how many buildings were restored; it also depends on whether the life that was there still has a place.

At dusk I went back to the river; the lights on the far bank began shifting and sightseeing boats passed one after another.

Before leaving, I took the ferry once more — the same two yuan, the same dozen minutes.

The first time I rode it, I thought I was travelling from the old city to the new one.

The second time I realized the order was the other way round: this boat carried a million people east first, and only then did those towers grow there.

The tallest tower today is six hundred and thirty-two metres; the boat that carried the people across costs two yuan a ticket and rides empty.

If you only had one day, would you go up the six-hundred-metre observation deck and look down over the city, or walk a lane that might not exist in a few years?